Quick update:
I was in the area so popped into Circuit Italia to check out the progress. I could only get a view of a small section but it looks like most of the track has been graded/smoothed out and doesn't look far from being sealed.
A lot of work has been done but it still heaps to go. I have no official time line but looks like it could be at least 6 months to 1 year away yet. If it is any sooner then GREAT! So cool to see it coming along.
Took some photo's of what I could see. These are the two corners in the top right hand of the circuit (closest to MG Car Club Hill climb).

Photo credit: Brett Davey from BSD Photography.
Not much action on here anymore, but I finally have something decent to report!
Round 6 NSW CAMS Supersprint Championships - Wakefield Park - New PB 1:03.84
That is a full second quicker than my old best time. Very stoked to get into the 1:03's, makes all the hard work on the aero worth it.
vid of one of the laps
Not the 1:03 as I achieved my PB on the 2nd last lap of the day! Camera battery was dead by then.

So apparently I have heard on the grapevine that a tender has been put to carry out construction of the track.
Just hearsay from a local, but construction should begin soon with a view to finish early-mid 2019. Google maps shows the outline of the track has been cleared/mapped out.
It's a slow process, and it's driving me crazy how long it has taken, but I'm sure it will be worth the wait.
circuit italia.bmp

Thanks to those still following! Appreciate all the feedback and comments.
Round 1 - NSW Supersprint Championship 3/3/18 - Finished 13th outright, and 2nd in class. Damn pesky EVO beat me! Very hot day - Lap time was down 2 secs off my PB. Still 1:43 not too bad.
New aero worked well, still need to fine tune it and need to explore the limits with more seat time. The car ran flawlessly with only needing to adjust the tyre pressures and keep adding fuel for the day.
Some pics from Saturday-
180303 m.smith smsp.bmp
180303 a.smith smsp.bmp

Thanks! I have to remake the diffuser and make the tunnel a little wider. I need to beef up the mounts and just make it overall stronger.
I too am a little concerned with temps, but luckily the car is only on track 10mins at a time.
If I ever did proper racing with 10-20 laps, it would need a rethink.
You have some more races planned for 2018?

Hey! Nice to hear from you too! Much happening in your world?
I'm hoping to do at least 6 supersprints this year.
Bought a new race seat and 6 point harness.
Hey! Nice to hear from you too! Much happening in your world?
I'm hoping to do at least 6 supersprints this year.
Bought a new race seat and 6 point harness.

G'day - Happy New Year All!
2018 is going to be sweet!
I took some pictures (attached), but it's very difficult to see all my hard work lol. I used rivnuts inserted into the chassis rails and then used bolts/washers to attach sheets of alucobond (aluminium and acrylic composite) to the underside. It's about 5mm thick. Pretty light and rigid. It runs from the front cross member to the rear diff. It is as wide as the chassis rails. (due to sheet size I got for free). Used t-piece extrusion bits to join the sheets.
Then my plywood front splitter joins the flat floor at the cross member. FRP diffuser joins at the rear diff. Had to cut out some bits to clear the exhaust in some sections, also helps with managing heat.
I wasn't expecting much difference on track as this was all untested and pretty slap together. I had some expectation my aero mods could have a negative result with the extra weight and possible extra drag. With no CFD or wind tunnel or even scale model tests, what could I expect?
As it turns out, the rear diffuser broke it's mounts from all of the load and downforce it generated. The positive outcome was I then removed the damaged diffuser and ran again without it.
Felt the lack of rear downforce immediately through turn 1 at approx. 180km/hr!!! The rear end stepped sideways on turn in. Talk about exciting way to enter turn 1!!!

Revised splitter, flat floor and rear diffuser all finished.
Tested it as SMSP GP circuit at NSW Supersprint with encouraging results.
I need to strengthen the mounts. So much downforce! Didn't expect it to work so good!

Oh man you have a Bunnings sponsorship??? So jealous! I have to pay out of pocket at Bunnings for all of my aero and general raw materials.
I scored some old signs at work from a defunct distributor. I'm going to use them for my flat floor. They are made of that alucobond stuff. Nothing beats free stuff.
I need to take the Silvia off the trailer and get set up. Then I can take some photo's and post them up.

Exhaust completed, much more clearance now.
The car is a little quieter and sounds better, not so much like a tractor anymore lol.
I didn’t go too fancy as I didn’t change the dump and front pipe. Turns out these parts aren’t 3 inch anyhow, apparently only 2.75 inch. I’d only change these if I went bigger turbo with external gate etc.
So no v-bands, just bolted it up to the existing flange off the front pipe.
The most angle in the system is 20 degrees and it’s all at the back to keep it up high.
Time to start messing about with under car aero now. Can't wait!! YEOWW!!!